change region ngrok code example

Example 1: ngrok config file

ngrok start --config=./ngrok.yml --all

Example 2: ngrok config file

authtoken: 4nq9771bPxe8ctg7LKr_2ClH7Y15Zqe4bWLWF9p
tunnels:
  myapp-http:
    addr: 80
    proto: http
    hostname: example.com
    bind_tls: false
  mypp-https:
    addr: 443
    proto: tls
    hostname: example.com